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This dataset contains csv files in support of the conclusions published in "Water use demand in Mediterranean California under multiple scenarios of developed and agricultural land use " in the journal PLOS One. We used the USGS's LUCAS model to examine a broad suite of spatially explicit future land use scenarios and their associated county-level water use demand, including the historical (1992-2011) and projected periods (2012-2062) across 40 Monte Carlo simulations.We examined a range of potential water demand futures sampled from a 20-year record of historical (1992-2012) data to develop a suite of potential future land change scenarios from 2012-2062. These scenario simulations include a 1) business-as-usual...
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Issue Title: Special Issue: Science Results from the Canadian International Polar Year 2007-2008 Tundra and taiga ecosystems comprise nearly 40 % of the terrestrial landscapes of Canada. These permafrost ecosystems have supported humans for more than 4500 years, and are currently home to ca. 115,000 people, the majority of whom are First Nations, Inuit and Métis. The responses of these ecosystems to the regional warming over the past 30-50 years were the focus of four Canadian IPY projects. Northern residents and researchers reported changes in climate and weather patterns and noted shifts in vegetation and other environmental variables. In forest-tundra areas tree growth and reproductive effort correlated with...
This dataset consists of the current distribution (2000s) of mangrove forests in the southeastern U.S. This dataset was created from the current best available mangrove data on a state specific basis. Florida mangrove data was extracted from Florida Landuse Land Cover Classification System (FLUCCS). For Louisiana, we used observations of mangrove stands from aerial surveys by Michot et al. (2010). Mangrove presence in Texas came from maps produced by Sherrod & McMillan (1981) and the NOAA Benthic Habitat Atlas of Coastal Texas (Finkbeiner et al. 2009). Please note that this map depicts the distribution of mangrove forests and not mangrove individuals. More detailed information on this dataset is available in Osland...
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This paper examines changes in climate with respect to permafrost and engineering design in Arctic regions. Current understanding of climate changes, predictive modeling, and climate data were studied. Inconsistencies and differences were noted, discussed, and evaluated using comparisons of the resulting climate data and graphs. A graphical analysis was done to compare different methods of data analysis and different visual interpretations of historical climate trends. The graphical analyses in this paper should be used as a guide for determining the accuracy of thermal design parameters applied to current project designs. The methodology used to evaluate raw data can greatly affect the output values used in design....
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Permanent electrode arrays were set up at ten monitoring sites from Whitehorse, Yukon, to Fort St. John, British Columbia, in order to gain a clearer perspective of the effectiveness of electrical resistivity tomography (ERT) monitoring over an annual cycle of freezing and thawing. This research forms part of a longer-term project that is attempting to use ERT to examine changes in permafrost resulting from climate change. Inter-site and intra-site variability were examined by installing and maintaining data-loggers to monitor active layer and shallow permafrost temperatures, air temperatures, and snow depths at each site from August 2010-August 2011. Additional site information was collected on each ERT survey...
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We investigated spatial variability in the community structure of stream macroinvertebrates at six reaches within Caribou-Poker Creeks Research Watershed in the Alaskan taiga forest. Stream reaches differed most notably in river continuum position (stream orders 1–4) and influence of permafrost. Permafrost may underly much of an entire watershed or may be only locally present in valley bottoms. Permafrost distribution influences hydrology, water temperature, and riparian vegetation. We sampled benthic macroinvertebrates six times during the ice-free season between June 1995 and June 1996. Mean invertebrate abundance (range: 1160–14494 individuals/ m2) was significantly different among sites, the lower values occurring...
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Understanding the role of permafrost in controlling groundwater flow paths and fluxes is central in studies aimed at assessing potential climate change impacts on vegetation, species habitat, biogeochemical cycling, and biodiversity. Recent field studies in interior Alaska show evidence of hydrologic changes hypothesized to result from permafrost degradation. This study assesses the hydrologic control exerted by permafrost, elucidates modes of regional groundwater flow for various spatial permafrost patterns, and evaluates potential hydrologic consequences of permafrost degradation. The Yukon Flats Basin (YFB), a large (118,340 km super(2)) subbasin within the Yukon River Basin, provides the basis for this investigation....
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The purpose of this study is to evaluate tsunami hazard for the community of Seward and northern Resurrection Bay area, Alaska. This report will provide guidance to local emergency managers in tsunami hazard assessment. We used a numerical modeling method to estimate the extent of inundation by tsunami waves generated from earthquake and landslide sources. Our tsunami scenarios included a repeat of the tsunami of the 1964 Great Alaska Earthquake, as well as tsunami waves generated by two hypothetical Yakataga Gap earthquakes in northeastern Gulf of Alaska, hypothetical earthquakes in Prince William Sound and Kodiak asperities of the 1964 rupture, and local underwater landslides in Resurrection Bay. Results of numerical...
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Potential tsunami hazards for the Fox Islands communities of Unalaska/Dutch Harbor and Akutan were evaluated by numerically modeling the extent of inundation from tsunami waves generated by hypothetical earthquake sources and taking into account historical observations. Worst-case hypothetical scenarios are defined by analyzing results of a sensitivity study of the tsunami dynamics related to various slip distributions along the Aleutian megathrust. The worst-case scenarios for Unalaska and Akutan are thought to be thrust earthquakes in the Fox Islands region with magnitudes ranging from Mw 8.8 to Mw 9.1 that have their greatest slip at 30-40 km (18-25 mi) depth. We also consider Tohoku-type ruptures and an outer-rise...
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Staff from Alaska Earthquake Center, Geophysical Institute and Alaska Division of Geological & Geophysical Surveys evaluated potential tsunami hazards for the city of Sand Point, on Popof Island in the Shumagin Islands archipelago. We numerically modeled the extent of inundation from tsunami waves generated by local and distant earthquake sources. We considered the results in light of historical observations. The worst-case scenarios are defined by analyzing results of the sensitivity study of the tsunami dynamics with respect to different slip distributions along the Aleutian megathrust. For the Sand Point area, the worst-case scenarios are thought to be thrust earthquakes in the Shumagin Islands region with magnitudes...
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This EnviroAtlas web service supports research and online mapping activities related to EnviroAtlas (https://www.epa.gov/enviroatlas). The Food, Fuel, and Materials category in this web service includes layers illustrating the ecosystems and natural resources that provide or support the production of food, fuel, or other materials, the need or demand for these items, the impacts associated with their presence and accessibility, and factors that place stress on the natural environment's capability to provide these benefits. EnviroAtlas allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the conterminous United States. Additional descriptive...
Types: Citation; Tags: 12-digit HUCs, Agriculture, Air, Alabama, Alaska, All tags...
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The evolution of permafrost in cold regions is inextricably connected to hydrogeologic processes, climate, and ecosystems. Permafrost thawing has been linked to changes in wetland and lake areas, alteration of the groundwater contribution to streamflow, carbon release, and increased fire frequency. But detailed knowledge about the dynamic state of permafrost in relation to surface and groundwater systems remains an enigma. Here, we present the results of a pioneering 1,800 line-kilometer airborne electromagnetic survey that shows sediments deposited over the past 4 million years and the configuration of permafrost to depths of 100 meters in the Yukon Flats area near Fort Yukon, Alaska. The Yukon Flats is near the...
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This thesis is an investigation of the biophysical controls on the three modes of methane (CH4 ) release from a boreal peatland: diffusion, plant-mediated transport and ebullition. My objectives were to (1) quantify the total CH4 flux of a permafrost thaw-affected peatland, (2) establish the relative importance of the three modes of CH4 release in these systems, and (3) identify key biotic and abiotic controls on individual transport mechanisms. Results showed that ebullition and plant-mediated transport were the dominant pathways for CH4 release and that traditional approaches for measuring total CH4 flux from peatland soils underestimated total efflux by not capturing ebullition. Further, results from a laboratory...
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Ecological models facilitate evaluation and assessment of alternative plans for restoring the Greater Everglades ecosystem. Modeling outputs were used in evaluations of alternative water control plans to be performed by the Combined Operational Plan (COP). The models used were: (1) Cape Sable Seaside Sparrow Marl Prairie Indicator in conjunction with (2) Cape Sable Seaside Sparrow Helper, (3) Florida apple snail (native) population model (EverSnail), (4) Wader Distribution Evaluation Modeling (WADEM), (5) Small-sized freshwater fish density, and (6) American alligator production probability (i.e., breeding potential). These ecological models are used to examine potential impacts on the above listed flora and fauna...
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This EnviroAtlas web service supports research and online mapping activities related to EnviroAtlas (https://www.epa.gov/enviroatlas). The Clean and Plentiful Water category in this web service includes layers illustrating the ecosystems and natural resources that filter and regulate water, the need or demand for clean and plentiful water, the impacts associated with water quality, and factors that place stress on water quality and supply. EnviroAtlas allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the conterminous United States. Additional descriptive information about each attribute in this web service is located within each web...
Types: Citation; Tags: 12-digit HUCs, Agriculture, Air, Alabama, Alaska, All tags...
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Boreal regions contain more than half of the carbon in forested regions of the world and over 60% of the world's surface freshwater. Carbon storage and the flood control and water filtration provided by freshwaters and wetlands have recently been identified as the most important ecosystem services provided by boreal regions, with a value many times greater than current resource exploitation. Ecosystem services and sensitive ways of detecting their impairment have so far not been fully included in boreal conservation planning. Climate warming, via its effect on permafrost melting, insect damage, and forest fire, threatens to trigger large positive carbon feedbacks that may enhance the concentrations of greenhouse...
map background search result map search result map EnviroAtlas - Clean and Plentiful Water Metrics for the Conterminous United States EnviroAtlas - Food, Fuel, and Materials Metrics for Conterminous United States Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Airborne electromagnetic imaging of discontinuous permafrost The effect of fire and permafrost interactions on soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: implications for post-thaw carbon loss Influence of permafrost distribution on groundwater flow in the context of climate-driven permafrost thaw: Example from Yukon Flats Basin, Alaska, United States Physical and ecological controls on methane release from a boreal peatland in interior Alaska Exploring the sensitivity of soil carbon dynamics to climate change, fire disturbance and permafrost thaw in a black spruce ecosystem Seasonal cycling in electrical resistivities at ten thin permafrost sites, southern Yukon and northern British Columbia “The Worst Thing We Had To Contend With”: Permafrost and Construction of the Alcan Highway Comprehensive conservation planning to protect biodiversity and ecosystem services in Canadian boreal regions under a warming climate and increasing exploitation Landscape patterns and stream reaches in the Alaskan taiga forest: potential roles of permafrost in differentiating macroinvertebrate communities Progress in space-borne studies of permafrost for climate science: Towards a multi-ECV approach Mediterranean California’s water use future based on scenarios of land use change 1992-2062 - Tabular Data Tsunami inundation maps of Seward and northern Resurrection Bay, Alaska Tsunami inundation maps of Fox Islands communities, including Dutch Harbor and Akutan, Alaska Tsunami inundation maps for the city of Sand Point, Alaska Ecological modeling output for the Combined Operational Plan Tsunami inundation maps for the city of Sand Point, Alaska Tsunami inundation maps of Seward and northern Resurrection Bay, Alaska Tsunami inundation maps of Fox Islands communities, including Dutch Harbor and Akutan, Alaska Landscape patterns and stream reaches in the Alaskan taiga forest: potential roles of permafrost in differentiating macroinvertebrate communities Physical and ecological controls on methane release from a boreal peatland in interior Alaska Ecological modeling output for the Combined Operational Plan Exploring the sensitivity of soil carbon dynamics to climate change, fire disturbance and permafrost thaw in a black spruce ecosystem Airborne electromagnetic imaging of discontinuous permafrost Influence of permafrost distribution on groundwater flow in the context of climate-driven permafrost thaw: Example from Yukon Flats Basin, Alaska, United States Seasonal cycling in electrical resistivities at ten thin permafrost sites, southern Yukon and northern British Columbia “The Worst Thing We Had To Contend With”: Permafrost and Construction of the Alcan Highway The effect of fire and permafrost interactions on soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: implications for post-thaw carbon loss Mediterranean California’s water use future based on scenarios of land use change 1992-2062 - Tabular Data Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Progress in space-borne studies of permafrost for climate science: Towards a multi-ECV approach Comprehensive conservation planning to protect biodiversity and ecosystem services in Canadian boreal regions under a warming climate and increasing exploitation EnviroAtlas - Clean and Plentiful Water Metrics for the Conterminous United States EnviroAtlas - Food, Fuel, and Materials Metrics for Conterminous United States